Piston Messed Up

I got a question. I installed a new bottom end and used my old top end/piston because it was running extremely good.

I drove it for about 2 months and it was powerful all the way to the end (today). Couple days ago I turned up the screw on the carburator to get it to idle without turning off and I had to turn it all the way. After that the engine was way louder and seemed to burn much better but today the piston got stuck in one moment while I was driving just after turning it on.

When I took the head off, I could see a little hole in the side of the piston from the top and the spark as well as the inside of the combustion chamber and the top of the piston was all black with rust - guessing it was running too rich.

I also can see metal scratching down from either the piston or the walls when I look through the exhaust opening. The piston is still stuck and I have to hammer is out tomorrow when its day again so I can buy a new top end. I just hope the crankshaft or bearings didnt get any damage.

Anyways. Is is possible all that happened because I changed it too rich? I personally dont think that makes any sense. It also doesnt seem like the regular case like when its too lean and first you lose power and compression before the engine goes down. It ran perfect, smooth and a second later OFF and stuck.

I also run it with open exhaust but I also dont think thats the reason. Maybe it was just old. Next time I only use synthetic oil again.

The pipe is on without muffler.

yeah just did that. I cant even get it out completely but it looks like something between the rings broke off because above the exhaust hole there is a huge scratch, if you can still call it scratch where the piston got stuck. i saw a picture in here of parts breaking off between the piston rins so i am pretty sure its that because there is no way anything can get in there. it was running perfectly with full power for 2 months after using the new bottom end. luckily the crankshaft seems fine. i guess it was just old as **** and i really used it almost daily and for long trips.

is this the christian forum or why i cant even use the word h e l l in here??? wtf

No, the pins were ok. It was something around the rings that must have broke off.

Oh ok. Well the piston was the last thing that still could break. Everything else on that bike I replaced with new or custom parts. I should have just bought a new engine or make my own bike instead of building up a used one but at least I learned some new things again.

It was the upper needle bearing that lost parts...

this is the old bearing:



unfortunately the NEW bottom end got some damage too so maybe its better to just get a new complete engine.

I just ordered the SkyHawk. From what I heard, that one seems good. i wonder if the extra power is really noticeable.